1. Field of the Invention
The present invention relates to the use of prophy angles in the field of dentistry for cleaning teeth, and, in particular, to an economically feasible disposable dental prophy angle having drive shaft coupling means including an upper drive shaft assembly with a finger-type clutch that engages a lower drive shaft assembly with a clutch receptacle located in a non-disposable prophy handpiece such that the coupling means minimizes wear exerted on the lower drive shaft assembly, and thus, maximizes the useful life of the prophy handpiece.
2. Discussion of the Prior Art
It is known to provide a dental prophy angle to polish and otherwise clean teeth. For example, it has long been the practice to provide prophy angles which engage a prophy handpiece, and are removable therefrom, to clean and polish the teeth of a person. Such removable prophy angles often house an upper drive shaft assembly which couples with the lower drive shaft assembly of the prophy handpiece when the prophy angle engages the prophy handpiece.
After being used to clean and polish the teeth of a person, the removable prophy angle is removed from the prophy handpiece and sanitized so as to avoid the spread of various contagious diseases and viruses. Because removable prophy angles are reusable, such prophy angles are often constructed of relatively durable, yet relatively expensive materials. However, removable prophy angles stand the risk of spreading contagious diseases and viruses if they are not properly sanitized between usage on different patients.
It is also known to provide a disposable dental prophy angle which is also removable from the prophy handpiece. Disposable prophy angles usually have the same design as the removable prophy angles; however, because such disposable prophy angles are used on only one patient and then discarded, disposable prophy angles are constructed of more economical materials. Disposable prophy angles offer a more effective method of preventing the spread of contagious diseases and viruses between successive patients, and also between the patient and the dentist or dental technician than do non-disposable prophy angles. Reference is made to my U.S. Pat. No. 3,740,853 issued Jun. 26, 1973; U.S. Pat. No. 3,869,877 issued Mar. 11, 1975; and U.S. Pat. No. 5,209,658 issued May 11, 1993.
In order for disposable prophy angles, to be economically feasible, they must be constructed of the aforementioned economical materials, examples of which include any of a number of synthetic resin materials suitable for such use. However, when constructed of such synthetic resin materials, the upper drive shaft assembly of a disposable prophy angle can cause damage to the lower drive shaft assembly of the non-disposable prophy handpiece when coupled thereto.
Therefore, a significant, and heretofore unsolved, problem exists to provide a coupling means for the drive shaft of a disposable prophy angle which minimizes the wear on, and increases the useful life of, the lower drive shaft assembly of a prophy handpiece while allowing the use of economical materials, such as any of a number of synthetic resin materials, in the construction of the upper drive shaft assembly of a disposable prophy angle.